;  CARVE-TEXT
;   Carving, embossing, & stamping
;   Process taken from "The Photoshop 3 WOW! Book"
;   http://www.peachpit.com


(define (carve-brush brush-size)
  (cond ((<= brush-size 5) "Circle (05)")
	((<= brush-size 7) "Circle (07)")
	((<= brush-size 9) "Circle (09)")
	((<= brush-size 11) "Circle (11)")
	((<= brush-size 13) "Circle (13)")
	((<= brush-size 15) "Circle (15)")
	((<= brush-size 17) "Circle (17)")
	((> brush-size 17) "Circle (19)")))

(define (carve-scale val scale)
  (* (sqrt val) scale))

(define (calculate-inset-gamma img layer)
  (let* ((stats (gimp-histogram layer 0 0 255))
	 (mean (car stats)))
    (cond ((< mean 127) (+ 1.0 (* 0.5 (/ (- 127 mean) 127.0))))
	  ((>= mean 127) (- 1.0 (* 0.5 (/ (- mean 127) 127.0)))))))

(define (script-fu-carved-logo text size font bg-img carve-raised padding)
  (let* ((img (car (gimp-file-load 1 bg-img bg-img)))
	 (offx (carve-scale size 0.33))
	 (offy (carve-scale size 0.25))
	 (feather (carve-scale size 0.3))
	 (brush-size (carve-scale size 0.3))
	 (b-size (+ (carve-scale size 0.5) padding))
	 (layer1 (car (gimp-image-get-active-drawable img)))
	 (mask-layer (car (gimp-text-fontname img -1 0 0 text b-size TRUE size PIXELS font)))
	 (width (car (gimp-drawable-width mask-layer)))
	 (height (car (gimp-drawable-height mask-layer)))
	 (mask-fs 0)
	 (mask (car (gimp-channel-new img width height "Engraving Mask" 50 '(0 0 0))))
	 (inset-gamma (calculate-inset-gamma img layer1))
	 (mask-fat 0)
	 (mask-emboss 0)
	 (mask-highlight 0)
	 (mask-shadow 0)
	 (shadow-layer 0)
	 (highlight-layer 0)
	 (cast-shadow-layer 0)
	 (csl-mask 0)
	 (inset-layer 0)
	 (il-mask 0))

    (gimp-context-push)

    (gimp-image-undo-disable img)

    (gimp-image-set-filename img "")

    (gimp-image-add-channel img mask 0)

    (gimp-layer-set-lock-alpha mask-layer TRUE)
    (gimp-context-set-background '(255 255 255))
    (gimp-edit-fill mask-layer BACKGROUND-FILL)
    (gimp-context-set-background '(0 0 0))
    (gimp-edit-fill mask BACKGROUND-FILL)

    (plug-in-tile 1 img layer1 width height FALSE)

    (gimp-edit-copy mask-layer)
    (set! mask-fs (car (gimp-edit-paste mask FALSE)))
    (gimp-floating-sel-anchor mask-fs)
    (if (= carve-raised TRUE)
	(gimp-invert mask))

    (gimp-image-remove-layer img mask-layer)

    (set! mask-fat (car (gimp-channel-copy mask)))
    (gimp-image-add-channel img mask-fat 0)
    (gimp-selection-load mask-fat)
    (gimp-context-set-brush (carve-brush brush-size))
    (gimp-context-set-foreground '(255 255 255))
    (gimp-edit-stroke mask-fat)
    (gimp-selection-none img)

    (set! mask-emboss (car (gimp-channel-copy mask-fat)))
    (gimp-image-add-channel img mask-emboss 0)
    (plug-in-gauss-rle 1 img mask-emboss feather TRUE TRUE)
    (plug-in-emboss 1 img mask-emboss 315.0 45.0 7 TRUE)

    (gimp-context-set-background '(180 180 180))
    (gimp-selection-load mask-fat)
    (gimp-selection-invert img)
    (gimp-edit-fill mask-emboss BACKGROUND-FILL)
    (gimp-selection-load mask)
    (gimp-edit-fill mask-emboss BACKGROUND-FILL)
    (gimp-selection-none img)

    (set! mask-highlight (car (gimp-channel-copy mask-emboss)))
    (gimp-image-add-channel img mask-highlight 0)
    (gimp-levels mask-highlight 0 180 255 1.0 0 255)

    (set! mask-shadow mask-emboss)
    (gimp-levels mask-shadow 0 0 180 1.0 0 255)

    (gimp-edit-copy mask-shadow)
    (set! shadow-layer (car (gimp-edit-paste layer1 FALSE)))
    (gimp-floating-sel-to-layer shadow-layer)
    (gimp-layer-set-mode shadow-layer MULTIPLY-MODE)

    (gimp-edit-copy mask-highlight)
    (set! highlight-layer (car (gimp-edit-paste shadow-layer FALSE)))
    (gimp-floating-sel-to-layer highlight-layer)
    (gimp-layer-set-mode highlight-layer SCREEN-MODE)

    (gimp-edit-copy mask)
    (set! cast-shadow-layer (car (gimp-edit-paste highlight-layer FALSE)))
    (gimp-floating-sel-to-layer cast-shadow-layer)
    (gimp-layer-set-mode cast-shadow-layer MULTIPLY-MODE)
    (gimp-layer-set-opacity cast-shadow-layer 75)
    (plug-in-gauss-rle 1 img cast-shadow-layer feather TRUE TRUE)
    (gimp-layer-translate cast-shadow-layer offx offy)

    (set! csl-mask (car (gimp-layer-create-mask cast-shadow-layer ADD-BLACK-MASK)))
    (gimp-layer-add-mask cast-shadow-layer csl-mask)
    (gimp-selection-load mask)
    (gimp-context-set-background '(255 255 255))
    (gimp-edit-fill csl-mask BACKGROUND-FILL)

    (set! inset-layer (car (gimp-layer-copy layer1 TRUE)))
    (gimp-image-add-layer img inset-layer 1)

    (set! il-mask (car (gimp-layer-create-mask inset-layer ADD-BLACK-MASK)))
    (gimp-layer-add-mask inset-layer il-mask)
    (gimp-selection-load mask)
    (gimp-context-set-background '(255 255 255))
    (gimp-edit-fill il-mask BACKGROUND-FILL)
    (gimp-selection-none img)

    (gimp-levels inset-layer 0 0 255 inset-gamma 0 255)

    (gimp-image-remove-channel img mask)
    (gimp-image-remove-channel img mask-fat)
    (gimp-image-remove-channel img mask-highlight)
    (gimp-image-remove-channel img mask-shadow)

    (gimp-drawable-set-name layer1 "Carved Surface")
    (gimp-drawable-set-name shadow-layer "Bevel Shadow")
    (gimp-drawable-set-name highlight-layer "Bevel Highlight")
    (gimp-drawable-set-name cast-shadow-layer "Cast Shadow")
    (gimp-drawable-set-name inset-layer "Inset")

    (gimp-display-new img)
    (gimp-image-undo-enable img)

    (gimp-context-pop)))

(script-fu-register "script-fu-carved-logo"
		    _"Carved..."
		    "Carve the text from the specified image.  The image will be automatically tiled to accomodate the rendered text string.  The \"Carve Raised Text\" parameter determines whether to carve the text itself, or around the text."
		    "Spencer Kimball"
		    "Spencer Kimball"
		    "1997"
		    ""
		    SF-STRING     _"Text" "Marble"
		    SF-ADJUSTMENT _"Font size (pixels)"  '(100 2 1000 1 10 0 1)
		    SF-FONT       _"Font"                "Engraver"
		    SF-FILENAME   _"Background image"
		                  (string-append ""
						 gimp-data-directory
						 "/scripts/images/texture3.jpg")
		    SF-TOGGLE     _"Carve raised text"   FALSE
		    SF-ADJUSTMENT _"Padding around text" '(10 0 1000 1 10 0 1))

(script-fu-menu-register "script-fu-carved-logo"
			 "<Toolbox>/Xtns/Logos")
